Future sailors: what will ships look like in 30 years?(theguardian.com) |
Future sailors: what will ships look like in 30 years?(theguardian.com) |
- LNG is definitely happening, and that alone will make a massive difference in emissions.
- No shit smoother bottoms and bulbous bows are better for efficiency, that's been standard practice for decades and large cargo ships are generally not that old.
- Counter rotating props are interesting, I could see that being a big win but the mechanical complexity might not be worth it. Cargo ships are generally kept pretty simple for reliability.
- I doubt we'll see widespread wind or solar power any time soon. The dynamics of wind turbines on top of a pitching platform get pretty wild quick. The energy density of solar doesn't seem high enough.
- Lol, get the fuck out of here with the idea of nuclear power for cargo ships. The US Navy doesn't even bother with that complexity for anything other than subs & carriers where it's the only viable option.
Hey, me too! I see you were at Electric Boat. I was at NAVSEA HQ at around the same, probably making your life difficult. :) Though I did surface combatants, not subs.
1) ridiculously low $ per kWh electricity from multi hundred megawatt scale photovoltaic plants may may cracking hydrogen from seawater economical. It takes a ton of power, but if your power is almost free, it can work.
2) store the hydrogen. This has its own technical problems but in terms of energy density can replace heavy fuel oil
3) power ships from massively parallel arrays of hydrogen fuel cells, driving electric thrusters such as current generation large azipods.
Or, if there is some amazing advancement in Wh stored per kilogram/cubic meter of battery, in battery technology generally, skip the hydrogen step and have short to medium range small cargo ships the size of "geared" containerships which recharge in a fashion similarly to the upcoming Tesla semi tractor.
An important, if often repeated point: Natural gas reduces emissions at the point of consumption; that may be balanced out by higher climate change impact when it's mined.
If someone has good, conclusive information on that issue, it would be appreciated.
So the ships produce more unburned hydrocarbons (smog precursors) and sulphur oxides (acid rain precursors).
So even if the total CO2 emissions are similar, the other toxics are still greatly reduced.
1. When methane is burned, the carbon dioxide emissions are about 30% lower per unit energy than when liquid fuels are burned (50 g/MJ for methane, vs abt 74 g/MJ for liquid fuels) 2. When LNG is produced, an additional ~10% CO2 is generated, via energy consumption in the gas liquefaction plant 3. Methane leakage from production plant and pipelines is estimated at about 3% of total. This adds a greenhouse gas effect of about 63% (since methane is ~21 times more potent than CO2, greenhouse-effect-wise). 4. Pollutants such as sulfur oxides and soot from natural gas combustion are essentially nil. Heavy fuel oil for ships can have a very high sulfur content.
Sooo... it is quite possible that natural gas use has a higher climate change impact, due to leakages. For other pollutants, natural gas produces less.
What do you mean by that? Natural gas is taken from oil wells, the exact same kind of holes in the ground that produce bunker fuel. It's the highest level on the refinery column.
Edit: Here is a picture of the gas market right now:https://en.wikipedia.org/wiki/Gas_flare#/media/File:Niger_De...
If LNG pans out we would move those fires into the engines of ships. It would probably be carbon-neutral up to the trucks that the pipe welders drove.
MV Barzan is a container ships that's 400 m x 58.6 m. If you take say 400m x 50m * 24% solar panels that's ~6500 HP in full sun. I know the engines are significantly larger than that but not sure how much they use at cruising speed.
Energy-saving concepts have been around for a long, long time. For example, I first heard about the use of kites[1] over a decade ago, yet the company that makes them is struggling to stay afloat.
The issue is that commercial ships are very expensive to build, even using parametric design — where you basically plug in your desired cargo capacity and get a complete blueprint in return. Also, margins for shipyards are razor-thin, so they need to keep production very consistent and predictable in order to stay profitable. So there is not much incentive for either shipyards or shipping companies to build ships that deviate from the standard, cookie-cutter designs.
Maybe the upcoming regulation will provide the necessary incentives, but even then it will take several decades for the majority of ships—which have a lifespan of 40+ years—to be replaced with the next generation.
(Former naval architect and merchant mariner.)
[1] https://en.wikipedia.org/wiki/SkySails
Edit: Maybe what's needed is an Elon Musk for shipping. Someone with the resources and guts to take a big gamble on a new technology in an industry that otherwise moves at a crawl.
While sailors' lives are important in themselves, what do you see as the connection to the issue at hand, reducing climate change impact?
> it will kill you
Every sailor dies? I don't understand what you're getting at.
I wonder if we could make unmanned cargo boats that spend most of their time drifting?
Drifting can be quite effective at long distance ocean transport. For an example look at the Friendly Floatees accident [1]. A ship accidentally lost 29 000 floating bath toys in the middle of the Pacific. Over the next 15 years they reached land in on both the Pacific and Atlantic coasts of North America, the Pacific coast of South America, Australia, and Europe, and came close to Japan.
I'm imagining a ship that drifts, occasionally using an engine to get into known currents that will help it toward its goal or avoid currents known to hurt.
Places where two or more significant currents pass through the same region could be used to route traffic. They could have tow ships stationed there that can move drifters between the currents
We could have a large fleet of such drift ships carrying suitable commodities with very little environmental impact, with a smaller fleet of normal cargo ships providing fast transport to fill in the gaps caused by the randomness of the drifting fleet arrivals.
The above idea is based on the proposals I've seen to do something similar in space. Briefly, there are orbits that can move an object from Lagrange points of one pair of bodies to Lagrange points of another pair using very little energy, but they can take a very long time.
The proposals are to start using those to regularly send supply ships to various moons and planets that we think we may want to send humans to later. Suppose the path to some particular moon takes 30 years. If we start sending supply ships down that path now, sending one every 6 months, say, then 30 years from now they start arriving. Then we can send the humans. The ship with the humans only needs to take enough supplies for the trip out, making the trip much more feasible.
There are already lots of hydrofoil passenger ferries where passengers pay a lot less than a plane ticket but more than a slow monohull ferry ticket to get to a destination a bit more quickly.
On land, you might send something across the country at 60 mph on a truck for $0.4 per ton if you don't want to wait for rail or pay for air, but as far as I know, no such middle ground exists for ocean freight.
There are certainly customers who can't afford and don't need next-day air, but would pay more to get components in perhaps 5 days (60 mph hydrofoil, 6000 mile Pacific crossing, plus a day to load/unload) instead of 5-8 weeks, if there was a business that catered to that.
The shipping sector is squeezed by regulations and fuel prices. If you burn a tonne per hour and it costs a thousand bucks, thats about 8 million bucks per year. If oil price goes up, shipping gets more expensive. Those with newer more efficient or alternative fuel using ships get hit less.
If oil price goes down, it is the opposite.
Regulations need to be predictable. Ship building projects take a long time. If you can be sure that your fuel costs will be high in the future, an investment in better efficiency will pay itself back in a shorter time.
Global navies have proved and refined nuclear power technology for their ships.
Why not apply this technology to the commercial sector, instead of carrying gallons of diesel?
For example, China is extremely good at manufacturing, Japan and South Korea are great at electronics manufacturing, Germany engineering disciplines, etc, etc. North America could do this but everything would be very expensive or impossible to source locally.
Also, what about food? Do you enjoy coffee? Well it got to North America on a ship. How about bananas? Same thing, that tropical fruit's year round availability is due to shipping logistics. The same thing applies to most "everyday" goods like chocolate, transistors, cotton, etc, etc.
Also, going back to China, they don't only manufacture cheap goods to be shipped to Wal-Mart. They are also a major farming and agriculture producer.
Have a gander at the America's Cup boats, for instance.
I’d expect gas and diesel to be used for airplanes and ships for a long long time.
Why couldn't private security be part of international freight? The costs for this security could be added to freight costs.
For example, Russian private security contractors successfully protected ships near Somalia - https://www.youtube.com/watch?v=4XJ0nblZjZE
>What happens if a container sinks near a popular beach? I doubt people want these kinds of risks.
Governmental navies don't experience these risks? Also, read this section about liabilities for private nuclear reactors: https://en.wikipedia.org/wiki/Nuclear_marine_propulsion#Civi...
That is so 1950s. https://en.wikipedia.org/wiki/NS_Savannah
Four have been built (by the US, Germany, Japan, and Russia), starting in the 1950s (one per decade from the 1950s to the 1980s), but it's never really caught on. The most recent built was refitted and returned to service in 2016, after having been decommissioned and awaiting disposal for nearly a decade, the rest have been scrapped.
I am more curious about the scale of savings and the costs of trying to have a solar on top of the ship.
> Every sailor dies? I don't understand what you're getting at.
He means that life at sea is one of managed risk. For starters the ocean itself is hostile to human life. The machine is is also filled with hazards that will kill you if they aren't properly managed: steam, ionizing radiation, CO and CO2 build-up, combustion exhaust gasses, high pressure hydraulics, seawater flooding, electric shock and electrolysis hazards, rotating machinery hazards, the list goes on.
The number of nuclear navies numbers in the single digits, and of those, only a handful use nuclear powered ships in any sort of numbers.
There's a large boom, not new at this point, in extracting natural gas via fracking. My understanding is that the process produces emissions with high impact on climate change.
Edit: If the concern is that the economics of NG are driving higher consumption, then you've got to realize that you could still reclaim the net win by doing some legal thing to halt consumption. The important variables here are damage per consumption and consumption: you want to lower both, but if an improvement in damage per consumption raises consumption you don't want to go back and make the damage per consumption worse. The only reasonable course of action if the damage was too high would be to go in and say, keep using the least-damaging fuel but you're going to have to burn less of it.
